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I remember back in the 90's that commercial planes would line up on the runway, stop, apply full power and then release the brake to take off.

Now I've been on flight where they've literally rolled from the taxiway straight onto the runway and then powered up without stopping.

Why has that changed? What were the reasons for the older style?

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  • $\begingroup$ Back then people were in less of a hurry. $\endgroup$ – fbynite Jan 23 '14 at 10:08
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    $\begingroup$ the older style lets the engine ramp up to max thrust earlier on the runway (on the starting point even) and get more speed over a shorter distance. $\endgroup$ – ratchet freak Jan 23 '14 at 11:00
  • $\begingroup$ @ratchetfreak Makes sense. So then why was it stopped? $\endgroup$ – Cameron MacFarland Jan 23 '14 at 15:34
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    $\begingroup$ @CameronMacFarland engines that ramp up faster and are more powerful which eliminates the need for a longer runway otherwise, and noise reduction $\endgroup$ – ratchet freak Jan 23 '14 at 15:40
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Whether to use a static or a rolling takeoff is usually at the discretion of the captain as long as performance is not an issue and ATC doesn't need you to wait on the runway.

Reasons to do a static takeoff include:

  • Less runway is required
  • Better obstacle clearance (mainly because of the earlier liftoff)
  • Takeoff engine power can be confirmed prior to brake release
  • ATC may require an aircraft to wait on the runway due to wake turbulence separation requirements
  • The aircraft manufacturer may not allow a rolling takeoff

Reasons to do a rolling takeoff:

  • There is sufficient runway available
  • Obstacles are not an issue
  • Takeoff engine power can be set relatively quickly and an abort can still be made at a low speed
  • They take less time to perform, and at busy airports this can mean getting another airplane or two out/in per hour
  • They offer more passenger comfort because of the smoother acceleration

Not all airplanes provide performance information for rolling take offs. In this case, a commonly used technique is to ensure that takeoff power is set by a certain point on the runway and adding that distance to your calculated takeoff roll for planning purposes.

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    $\begingroup$ your bullets are correct. I believe the really telling one is that they take less time. Time is $$. Having said that, I fly as a passenger out of LaGuardia frequently, and when using runway 13 it is about 50-50 that the pilot will use a classic short field technique: stop in position, brakes on, power up, brake release, and go. $\endgroup$ – Skip Miller Jan 23 '14 at 17:17
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    $\begingroup$ FWIW, if the tower order was to line up and hold, we would do a static takeoff, although certainly not hold the breaks while takeoff power was being brought up unless performance required it. If the tower clearance was cleared for takeoff (without any line up and hold), we always did a rolling takeoff. $\endgroup$ – Terry Jan 23 '14 at 17:24
  • $\begingroup$ @Terry Good point, I have added line up and wait to my answer! $\endgroup$ – Lnafziger Jan 23 '14 at 17:33
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    $\begingroup$ Though not common among modern airplanes, there have been a few aircraft where a static takeoff was a manufacturer requirement. Concorde comes to mind. $\endgroup$ – Bret Copeland Jan 23 '14 at 17:54
  • $\begingroup$ @BretCopeland Added, thanks! $\endgroup$ – Lnafziger Jan 23 '14 at 19:40

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